London, 11. November 2015. Minsk's gay bar is pretty unusual, as nightspots go. It's a workers' café by day, where factory labourers drink their soup in conditions that have hardly changed since the Soviet era. But by night, it turns into an illicit bacchanal, filled with the LGBT people that Belarus's repressive government tries its best to pretend don't exist. "Minsk 2011", one of the opening performances of Belarus Free Theatre's "Staging A Revolution"-Festival in London, brings this secret world to life, as well as telling the stories of the hordes of sex workers that fill Minsk's streets as darkness falls.

Speaking to Natalia Kaliada (the company's co-founder, along with her husband Nikolai Khalezin) later, I learn that the company's work is structured round "a list we made of 16 taboo topics in Belarus. They cover everything from issues of religion and sexual minorities, to World War Two, political kidnappings, murders, the economic situation. We agreed that every single show we would make would be a theatrical explosion of one of these taboos."

Brave theatre company

Belarus's President Lukashenko presides over the small, landlocked Eastern European country with a style of government he publicly describes as 'authoritarian'. With similar honesty, the country's secret police are still called the KGB decades after the fall of the Soviet Union, and their methods haven't changed. For continuing to operate covertly under a regime whose opponents are routinely jailed, beaten, blacklisted and threatened, Belarus Free Theatre have been called "the bravest theatre company in the world".

The stakes are high for the members of Belarus Free Theatre who remain in the country, operating in secret. Kaliada tells me that "it's impossible to pretend that the authorities do not know the people who make up Belarus Free Theatre. But every single member of our company made their choice to be part of it, and they understand the consequences. They have already been arrested, lost their jobs, and some of them have lost their education." Kaliada and Khalezin run rehearsals and acting workshops via Skype, and fly performers out at staggered times and locations to covertly join them for the festival in London. Kaliada finds that "we live in two parallel realities: we work with our students in Belarus every day, and then work in our London reality too. It's not possible to be detached."

The country still exercises an emotional tug, but it's a complicated one. The script of "Minsk 2011" movingly talks about the country as a void: no coast, no natural resources, no jobs, no hope. And with the KGB's operations continuing uninterrupted since the fall of the Soviet Union, there's also a lack of the cultural heritage that comes with intellectual freedom. Vladimir Shcherban lost his job as a director at the Belarus National Theatre thanks to his decision to stage Sarah Kane's play in 2005: “It was a terrible scandal. I got asked to come in for a talk, and the theatre director looked into my eyes and said it's a load of bullshit you've dropped us into now."

As Kaliada told me, "straight away it was clear that we had to find playwrights to explore these taboos, but in Belarus the texts didn't really exist. When it came to '4:48 Psychosis' it was a chance for us to talk about sexuality, mental illness, suicide...by using the text of a British playwright, it was possible to talk about ourselves. And these plays gave us a lesson in how to talk about ourselves, too, and afterwards we started to make shows based on our actors' own experiences."

Testimonial of a survival fight

Nine of the festival's 10 performances are revivals of works the company has made during its decade in action. As such, they're a kind of record of survival against overwhelming odds. A document of a constantly evolving political situation. They've included new works such as the undeniably powerful Generation Jeans, a monologue by writer Nikolai Khalezin which discusses the fetishization of forbidden American clothes and music under Soviet rule as well as his harrowing arrest, soundtracked by a live DJ. Other works are riffs on classics, too: a staging of "King Lear" that heightened its folktale logic and turned the daughters' competition for their father's love into a striptease straight out of a Belarusian nightclub.

In Belarus, the company's performances must be staged covertly: in private apartments, street cafes, or even out in the woods. The first week of the 'Staging A Revolution' festival tries to replicate this atmosphere of secrecy. Audience members receive a text message on the day of the performance which directs them to a carefully selected secret location: a disused prison, tunnels underground, or a historic gay pub. We bring passports, as we'd be asked to in Belarus, in case of a police raid. The signs inside are in Russian, as are the performances – we squint round pillars at projected subtitles. After the performance, we drink and eat together (brown bread and beetroot soup) before a post-show discussion from invited activists. In Belarus, spaces of openness like these are rare, and to be treasured – audiences talk late into the night, relishing the atmosphere of honest conviviality in a country where, as Kaliada explains, even making eye contact with a passing stranger for more than a couple of seconds could start a fight.

Jailed journalists

In a split that reflects the parallel lives of the company's founders, the second week of the festival takes place in the Young Vic theatre, which Kaliada, Khalezin and Shcherban use as a base – the theatre's artistic director, David Lan, has described the threats of life in Belarus as similar to life in apartheid-era South Africa, where he grew up. In the bustling atmosphere of the theatre's studio, they present the new work that forms the centrepiece of the festival, "Time of Women". It tells the story of three female journalists and activists who were confined to prison after the disputed presidential elections of 2010.

It opens with a harrowing live recording of the PEN Pinter prize-winning journalist Irina Khalip married to one of the main opposition candidates, Andrei Sannikov. She describes in a broadcast live on air during an interview with Moscow radio station Ekho Moskvy, her arrest as she and her husband sought medical treatment for beatings during a peaceful protest. These women are real life heroes. But the play emphasises a somewhat traditional view of femininity: they long for husbands, children, houses, and to wear skirts again.

I'm With The Banned

Belarus Free Theatre's work is marked by paradoxes. Their method of working could only be possible in the internet age, relying on Skype to bring the company together and on livestreaming to reach an international audience of dissidents within Belarus as well as spectators around the world. But their theatrical idiom is, by comparison, rather straightforward. Their plays rely on raw emotionalism, on an aesthetic that feels by turns truthful and naive: particularly in New York '79, a staging of Kathy Acker's tale of gross and glitzy sexuality in a decaying city, which they turn into a kind of cabaret fairytale.

Festival Poster

The work comes into its own when it reveals truths about Belarus, rather than about far-off times and cities. "Time Of Women" is most moving as it reveals the small moments of compassion that mark prison life: the women yell out folk songs to hide their cellmate's shame at using a communal toilet bucket in the cell, and argue with secret police for packets of lard, as well as their freedom. This mix of humour, pragmatism, and absolute horror transfers over to the company's approach in staging the festival. Kaliada introduced one performance in a t-shirt, badge and tote bag bearing the company's logo, designed by Chinese artist and dissident Ai Weiwei, encouraging the audience to buy merchandise. David Gilmour, formerly of Pink Floyd, and Neil Tennant performed alongside them on stage at a one-off concert in October, punningly called "I'm With The Banned", In an even more disconcerting piece of tongue-in-cheek humour, the company's supporters are invited to "Get Blacklisted" by joining its new sponsorship program. In the celebratory atmosphere of the Young Vic, tucking into Belarusian herring canapes, it was hard not to feel a level of discomfort. Was it tasteless to the suffering of people in Belarus to be playing at dissidence, consequence free?

Theatrical explosion

As the fate of Syrian refugees exercises governments across Europe, it feels especially relevant to think about how stories of dissidence from around the world are told. Looking at the London theatre scene, you can't escape the answer: "very rarely". Freedoms in Russia and Ukraine are being eroded, not just Belarus, even as the story of the Soviet Union is taught in schools as a chapter of history that's been firmly closed.

Belarus Free Theatre is livestreaming the whole "Staging a Revolution" festival on its Ministry of Counterculture website, providing an alternative kind of education to the Soviet-tinged, heavily censored narratives on offer in Belarus's schools and mainstream media. And the company invites audiences around the world to join in by hosting the revolutionary equivalent of Eurovision parties, with the help of a pack of posters and feedback forms. It's a media machine on an impressive scale, outdoing Belarus's moribund state press as well as reflecting the increasingly blurred lines between theatre and cinema – and one that threatens to outshine the plays themselves.

The Staging A Revolution festival is, just as Kaliada hoped, a theatrical explosion. It blows up tiny moments of interaction – between performers and small audiences in tucked away venues in Belarusian woods or apartments – and scatters them across Europe, or worldwide. And that's the Belarus Free Theatre contradiction, all over. Small scale work made by people on the margins is brought into the mainstream because it's part of a huge, huge story. Of censorship, marginalisation, denial of sexual minorities' rights, of a European pariah state that's either forgotten or lauded as an offbeat tourist haven. The company's work doesn't always have the polished sheen to reflect the glare of public attention it gets – and under the challenging circumstances of its production, it never could. But it's got the stark power of a searchlight, focused on a corner of Europe that shouldn't be allowed to go dark.

Alice Saville is a British freelance arts journalist who regularly reviews, interviews and features for Auditorium magazine, Fest, and Exeunt. She is also a contributing editor at Exeunt, and organises the site's theatre design coverage.